Use defined constant values of trace

Author: Rot127

contrib/plugins/bap-tracing/frame_buffer.c

@@ -87,15 +87,13 @@ static bool std_frame_add_operand(StdFrame *std_frame, OperandInfo *oi) {
   return true;
 }
 
-FrameBuffer *frame_buffer_new(size_t size) {
+FrameBuffer *frame_buffer_new(void) {
   FrameBuffer *fb = g_malloc0(sizeof(FrameBuffer));
-  fb->fbuf = g_malloc0(sizeof(Frame *) * size);
-  fb->max_size = size;
   return fb;
 }
 
 bool frame_buffer_is_full(const FrameBuffer *buf) {
-  return buf->idx + 1 >= buf->max_size;
+  return buf->idx + 1 >= frames_per_toc_entry;
 }
 
 void frame_buffer_close_frame(FrameBuffer *buf) {
@@ -162,7 +160,7 @@ bool frame_buffer_is_empty(const FrameBuffer *buf) {
 }
 
 void frame_buffer_flush_to_file(FrameBuffer *buf, WLOCKED FILE *file) {
-  for (size_t i = 0; i <= buf->idx && i < buf->max_size; ++i) {
+  for (size_t i = 0; i <= buf->idx && i < frames_per_toc_entry; ++i) {
     Frame *frame = buf->fbuf[i];
     size_t msg_size = frame__get_packed_size(frame);
     uint8_t *packed_buffer = g_alloca(msg_size);
@@ -172,7 +170,7 @@ void frame_buffer_flush_to_file(FrameBuffer *buf, WLOCKED FILE *file) {
     buf->frames_written++;
     frame_free(frame);
   }
-  memset(buf->fbuf, 0, sizeof(Frame *) * buf->max_size);
+  memset(buf->fbuf, 0, sizeof(buf->fbuf));
   buf->idx = 0;
   // toc_update(); ??
 }

contrib/plugins/bap-tracing/frame_buffer.h

@@ -9,6 +9,7 @@
 #include <stdio.h>
 
 #include "frame.piqi.pb-c-patched.h"
+#include "trace_consts.h"
 #include "trace_meta.h"
 
 typedef enum {
@@ -17,17 +18,16 @@ typedef enum {
 } OperandAccess;
 
 typedef struct {
-  Frame **fbuf;          ///< The frames buffered.
-  size_t idx;            ///< Points to currently open frame.
-  size_t max_size;       ///< Maximum number of elements fbuf can hold.
+  Frame *fbuf[FRAMES_PER_TOC_ENTRY_]; ///< The frames buffered.
+  size_t idx;                         ///< Points to currently open frame.
   size_t frames_written; ///< Number of frames written from buffer to file.
 } FrameBuffer;
 
 /**
  * \brief Initializes a frame buffer with space for \p size frames.
  * Returns the buffer or NULL in case of failure.
  */
-FrameBuffer *frame_buffer_new(size_t size);
+FrameBuffer *frame_buffer_new(void);
 
 void frame_buffer_flush_to_file(FrameBuffer *buf, WLOCKED FILE *file);
 bool frame_buffer_is_full(const FrameBuffer *buf);

contrib/plugins/bap-tracing/trace_consts.h

@@ -6,14 +6,20 @@
 // Trace header constants
 
 static const uint64_t magic_number = 7456879624156307493LL;
-static const uint64_t magic_number_offset = 0LL;
-static const uint64_t trace_version_offset = 8LL;
-static const uint64_t bfd_arch_offset = 16LL;
-static const uint64_t bfd_machine_offset = 24LL;
-static const uint64_t num_trace_frames_offset = 32LL;
-static const uint64_t toc_offset_offset = 40LL;
-static const uint64_t first_frame_offset = 48LL;
-static const uint64_t out_trace_version = 2LL;
+
+static const uint64_t offset_magic_number = 0LL;
+static const uint64_t offset_trace_version = 8LL;
+static const uint64_t offset_target_arch = 16LL;
+static const uint64_t offset_target_machine = 24LL;
+static const uint64_t offset_frames_per_toc_entry = 32LL;
+static const uint64_t offset_toc_index_offset = 40LL;
+static const uint64_t offset_toc_start = 48LL;
+static const uint64_t offset_first_frame = 48LL;
+
+static const uint64_t trace_version = 3LL;
+
+#define FRAMES_PER_TOC_ENTRY_ 64LL
+static const uint64_t frames_per_toc_entry = FRAMES_PER_TOC_ENTRY_;
 
 // Arch specific
 

contrib/plugins/bap-tracing/tracing.c

@@ -152,7 +152,7 @@ static void vcpu_init(qemu_plugin_id_t id, unsigned int vcpu_index) {
   }
   g_ptr_array_insert(state.vcpus, vcpu_index, vcpu);
 
-  FrameBuffer *vcpu_frame_buffer = frame_buffer_new(FRAME_BUFFER_SIZE_DEFAULT);
+  FrameBuffer *vcpu_frame_buffer = frame_buffer_new();
   g_ptr_array_insert(state.frame_buffer, vcpu_index, vcpu_frame_buffer);
 
   g_rw_lock_writer_unlock(&state.frame_buffer_lock);
@@ -208,14 +208,14 @@ static bool write_header(FILE *file, const char *target_name) {
     qemu_plugin_outs("Failed to get arch/mach.\n");
     return false;
   }
-  uint64_t num_frames = 0ULL;
-  uint64_t toc_off = 0ULL;
+  uint64_t num_toc_entries = 0ULL;
+  uint64_t toc_index_offset = 0ULL;
   WRITE(magic_number);
-  WRITE(out_trace_version);
+  WRITE(trace_version);
   WRITE(frame_arch);
   WRITE(frame_mach);
-  WRITE(num_frames);
-  WRITE(toc_off);
+  WRITE(num_toc_entries);  // Gets updated later
+  WRITE(toc_index_offset); // Gets updated later
   return true;
 }
 

contrib/plugins/bap-tracing/tracing.h

@@ -106,8 +106,6 @@ static struct arch_enum_entry arch_map[] = {
 
 QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION;
 
-#define FRAME_BUFFER_SIZE_DEFAULT 1024
-
 /**
  * \brief VLIW architecture have instructions longer than 4 or 8bytes.
  */